It is known to use ultraviolet (UV) radiation in sterilisation systems for use in the purification of water and the sanitisation of a variety of items. The UV radiation and any ozone produced by the UV radiation with oxygen in the air acts to kill bacteria and germs. It is also known to use ultraviolet (UV) radiation for a variety of other uses including those involving the promotion of photochemical reactions and of molecular dissociation.
Conventional systems employ microwave energy to excite the source of UV radiation. One problem such systems is that it is difficult to efficiently provide sufficient excitation energy to the UV source and difficult to effectively transfer that energy to the substance or entity to be treated. It is therefore difficult to arrange systems for high energy, high throughput industrial purposes.
There is now described an ultraviolet light source which enables efficient, high throughput UV treatment to be conducted. The ultraviolet light source comprises an UV lamp which is excited by a microwave energy source. The lamp is enclosed by a waveguide comprising UV transparent material.
PCT Patent Applications Nos. WO 00/32244 and WO 01/09924 (in the name of the Applicant) describe non-pulsed ultraviolet light sources. The pulsed ultraviolet light sources of the present invention have been found to provide for enhanced efficacy (e.g. enhanced sterilising capability) and reduced power consumption when compared to the earlier described, non-pulsed ultraviolet light sources.